The correct answer to this open question is the following.
Your question is incomplete. It does not include the reference, the words of the President, or further context and references. It also does not include the options for this question.
However, doing some research we can say the following.
If you are referring to the words expressed by President Dwight Eisenhower regarding Dr. Salk, then the answer would be the following.
US President Dwight Eisenhower considered Dr. Jonas Salk as a true hero. President Eisenhower praised the work and accomplishments of Dr. Salk and the benefits for humanity. The President was specifically referring to the vaccine to prevent paralytic poliomyelitis. Dr. Salk's research helped other nations to develop knowledge to help their citizens, providing different forms to control the disease.
President Eisenhower strongly concluded that Dr. Salk was a benefactor of humanity. This presidential recognition happened on April 22, 1955.